1. Field of the Invention
The present invention generally relates to a semiconductor process including at least one of an implanting procedure. In particular, the present invention is directed to a semiconductor implanting process carried out in a cryogenic procedure below −30° C. to prevent the epitaxial material from forming dislocations.
2. Description of the Prior Art
Implanting procedures are usually employed in the conventional semiconductor processes to implant the needed dopant. Although the implantation of the dopant comes with the benefits of adjustment of the electrical properties of the semiconductor elements, the damages on the materials coming with the implantation of the dopant usually make the elements more susceptible to unintended effects. In order to solve the dilemma, this technical field thus develops a precise damage engineering. This enhancing amorphization technique enhances the amorphization by implantation to later reduce the residual damage post-anneal. A conventional approach is called a pre-amorphization implant, PAI for short, to form a specific amorphous region on a target material.
However, the pre-amorphization implant method still has some drawbacks. For example, although the pre-amorphization implant method is able to form a specific amorphous region on a target material, the lattice of the target material is also likely to suffer collateral damages, to form dislocations for instance. Dislocation flaws may result in the low junction leakage. Further, in a later rapid thermal step it is possible to encounter the relaxation of the stress in the epitaxial material.
In the light of the above, a novel semiconductor process is still needed. In particular, a novel semiconductor implantation process is still needed to prevent the epitaxial material form dislocation flaws after the pre-amorphization implanting step.